No one is born a Christian. No one can simply choose to become a Christian. No one becomes a Christian merely by trying to behave like one. A Christian is not someone who is necessarily religious.
The Bible reveals to us that without Christ, we are "dead in sins" (Ephesians 2:1-4). But becoming a Christian means that we have been "made alive" (Ephesians 2:5). Therefore, Jesus doesn't just make 'bad' people 'good', He makes 'dead' people 'live'!
This is entirely a spiritual experience which has implications for our everyday lives. After becoming a Christian we think differently, act differently and feel differently towards others. This result is called "conversion". Any unconverted soul cannot reasonably be expected to claim that they are a Christian!
For you to be reading this indicates that something is stirring in your soul. Perhaps you recognise your need for Christ? The Bible says that if you call upon the Lord for salvation you will be saved. I invite you to do this.
Becoming a Christian... 
Christianity is a spiritual identity. It is not gained by choice, behaviour, or heritage. It is a complete change of identity spiritually. This new identity is best referred to as being "in Christ". It can only occur in response to the Father calling, revealing, and redeeming. This is an act of grace. There is nothing you can do earn it or even activate it. It is entirely about God's gift being birthed in your soul.